She wrote: “I write this through tears of frustration and sadness that I have to postponed my concert tonight due to being very, very sick and with swollen vocal cords.”

“If I go on tonight and injure my vocal cords any more I could potentially have to cancel the rest of the tour.”

“I’m so, so sorry to disappoint any of my fans in London that have travelled hours to be here by plane or car and to all of the fans that got these tickets for a special occasion.”

Demi went on to say she had rescheduled the concert and said she would be coming back to the UK.

She was inundated with supportive messages from her fans, with one telling her they were praying for her to get better.

Another commented: “Your health comes first. Always.”

While a third said: “Feel better soon… We love you so much Queen.”

After making her debut as a child actress in “Barney and Friends” in 2002, Demi rose to prominence in 2008 when she starred in the Disney Channel television film “Camp Rock” and released her debut single “This Is Me” which peaked at number nine on the Billboard Hot 100.

After gaining international fame, she went on to be judge on the “X Factor” US in 2012.

Demi then made the switch from TV and film, to be a popstar.

Her biggest songs to date include “Confident” and “Let It Go,” plus her recent hit “Sorry Not Sorry.”